Method and device for supporting multiple uplink carrier access in wireless communication system

This application is based on and claims priority under 35 U.S.C. § 119 to Korean Patent Application No. 10-2022-0171291, which was filed in the Korean Intellectual Property Office on Dec. 9, 2022, the entire disclosure of which is incorporated herein by reference.

The disclosure relates generally to a wireless communication system, and more particularly, to a method and device for supporting multiple uplink carrier access and uplink transmission power control in a wireless communication system.

Considering the development of wireless communication from generation to generation, the technologies have been developed mainly for services targeting humans, such as voice calls, multimedia services, and data services. Following the commercialization of 5G (5th-generation) communication systems, it is expected that the number of connected devices will exponentially grow. Increasingly, these will be connected to communication networks. Examples of connected things may include vehicles, robots, drones, home appliances, displays, smart sensors connected to various infrastructures, construction machines, and factory equipment. Mobile devices are expected to evolve in various form-factors, such as augmented reality glasses, virtual reality headsets, and hologram devices. In order to provide various services by connecting hundreds of billions of devices and things in the 6G (6th-generation) era, there have been ongoing efforts to develop improved 6G communication systems. For these reasons, 6G communication systems are referred to as beyond-5G systems.

6G communication systems, which are expected to be commercialized around 2030, will have a peak data rate of tera (1,000 giga)-level bps and a radio latency less than 100 μsec, and thus will be 50 times as fast as 5G communication systems and have the 1/10 radio latency thereof.

In order to accomplish such a high data rate and an ultra-low latency, it has been considered to implement 6G communication systems in a terahertz band (for example, 95 GHz to 3 THz bands). It is expected that, due to severer path loss and atmospheric absorption in the terahertz bands than those in mmWave bands introduced in 5G, technologies capable of securing the signal transmission distance (that is, coverage) will become more crucial. It is necessary to develop, as major technologies for securing the coverage, radio frequency (RF) elements, antennas, novel waveforms having a better coverage than orthogonal frequency division multiplexing (OFDM), beamforming and massive multiple input multiple output (MIMO), full dimensional MIMO (FD-MIMO), array antennas, and multiantenna transmission technologies such as large-scale antennas. In addition, there has been ongoing discussion on new technologies for improving the coverage of terahertz-band signals, such as metamaterial-based lenses and antennas, orbital angular momentum (OAM), and reconfigurable intelligent surface (RIS).

Moreover, in order to improve the spectral efficiency and the overall network performances, the following technologies have been developed for 6G communication systems: a full-duplex technology for enabling an uplink transmission and a downlink transmission to simultaneously use the same frequency resource at the same time; a network technology for utilizing satellites, high-altitude platform stations (HAPS), and the like in an integrated manner; an improved network structure for supporting mobile base stations and the like and enabling network operation optimization and automation and the like; a dynamic spectrum sharing technology via collision avoidance based on a prediction of spectrum usage; an use of artificial intelligence (AI) in wireless communication for improvement of overall network operation by utilizing AI from a designing phase for developing 6G and internalizing end-to-end AI support functions; and a next-generation distributed computing technology for overcoming the limit of UE computing ability through reachable super-high-performance communication and computing resources (such as mobile edge computing (MEC), clouds, and the like) over the network. In addition, through designing new protocols to be used in 6G communication systems, developing mechanisms for implementing a hardware-based security environment and safe use of data, and developing technologies for maintaining privacy, attempts to strengthen the connectivity between devices, optimize the network, promote softwarization of network entities, and increase the openness of wireless communications are continuing.

It is expected that research and development of 6G communication systems in hyper-connectivity, including person to machine (P2M) as well as machine to machine (M2M), will allow the next hyper-connected experience. Particularly, it is expected that services such as truly immersive extended reality (XR), high-fidelity mobile hologram, and digital replica could be provided through 6G communication systems. In addition, services such as remote surgery for security and reliability enhancement, industrial automation, and emergency response will be provided through the 6G communication system such that the technologies could be applied in various fields such as industry, medical care, automobiles, and home appliances.

The disclosure provides a method and device for supporting AI-based multiple uplink carrier access and uplink transmission power control in a wireless communication system.

According to an embodiment of the disclosure, a method by a UE in a wireless communication system is provided. The UE receives, from a base station, AI model setup information for estimating AI-based UL pathloss. The UE estimates the AI-based UL pathloss for a base UL carrier based on the AI model setup information.

According to an embodiment of the disclosure, a UE for use in a wireless communication system is provided. The UE includes a memory and a processor connected to the memory. The processor may be configured to receive, from a base station, artificial intelligence AI model setup information for estimating AI-based UL pathloss, and estimate the AI-based UL pathloss for a base UL carrier based on the AI model setup information.

Embodiments of the disclosure are described in detail with reference to the accompanying drawings. The same or similar components may be designated by similar reference numerals although they are illustrated in different drawings. Detailed descriptions of constructions or processes known in the art may be omitted to avoid obscuring the subject matter of the disclosure.

Some elements may be exaggerated or schematically shown. The size of each element does not necessarily reflect the real size of the element.

Advantages and features of the disclosure and methods for achieving the same may be understood through the embodiments to be described below taken in conjunction with the accompanying drawings. However, the disclosure is not limited to the embodiments herein, and various changes may be made thereto. The embodiments herein are provided only to inform one of ordinary skilled in the art. The disclosure is defined only by the appended claims. The terms used herein are defined considering the functions in the disclosure and may be replaced with other terms according to the intention or practice of the user or operator. Therefore, the terms should be defined based on the overall disclosure.

The blocks in each flowchart and combinations of the flowcharts may be performed by computer program instructions. Since the computer program instructions may be equipped in a processor of a general-use computer, a special-use computer or other programmable data processing devices, the instructions executed through a processor of a computer or other programmable data processing devices generate means for performing the functions described in connection with a block(s) of each flowchart. Since the computer program instructions may be stored in a computer-available or computer-readable memory that may be oriented to a computer or other programmable data processing devices to implement a function in a specified manner, the instructions stored in the computer-available or computer-readable memory may produce a product including an instruction means for performing the functions described in connection with a block(s) in each flowchart. Since the computer program instructions may be equipped in a computer or other programmable data processing devices, instructions that generate a process executed by a computer as a series of operational steps are performed over the computer or other programmable data processing devices and operate the computer or other programmable data processing devices may provide steps for executing the functions described in connection with a block(s) in each flowchart.

Further, each block may represent a module, segment, or part of a code including one or more executable instructions for executing a specified logical function(s). Further, it should also be noted that in some replacement execution examples, the functions mentioned in the blocks may occur in different orders. For example, two blocks that are consecutively shown may be performed substantially simultaneously or in a reverse order depending on corresponding functions.

As used herein, the term “unit” refers to a software element or a hardware element such as a field-programmable gate array (FPGA) or an application specific integrated circuit (ASIC). A unit plays a certain role. However, the term “unit” is not limited to a software or hardware element. A unit may be configured in a storage medium that may be addressed or may be configured to reproduce one or more processors. Accordingly, as an example, a unit includes elements, such as software elements, object-oriented software elements, class elements, task elements, processes, functions, attributes, procedures, subroutines, segments of program codes, drivers, firmware, microcodes, circuits, data, databases, data architectures, tables, arrays, and variables. A function provided in an element or a unit may be combined with additional elements or may be split into sub elements or sub units. Further, an element or a unit may be implemented to reproduce one or more CPUs in a device or a security multimedia card. According to embodiments, a unit may include one or more processors.

As used herein, each of the phrases as “A or B”, “at least one of A and B”, “at least one of A or B”, “A, B, or C”, “at least one of A, B, and C”, and “at least one of A, B, or C,” may include all possible combinations of the items enumerated together in a corresponding one of the phrases. As used herein, such terms as “1st” and “2nd”, or “first” and “second” may be used to simply distinguish a corresponding component from another, and does not limit the components in another aspect (e.g., importance or order).

Wireless communication systems evolve beyond voice-centered services to broadband wireless communication systems to provide high data rate and high-quality packet data services, such as 3rd generation partnership project (3GPP) high speed packet access (HSPA), long term evolution (LTE) or evolved universal terrestrial radio access (E-UTRA)), LTE-advanced (LTE-A), LTE-pro, 3GPP2 high rate packet data (HRPD), ultra-mobile broadband (UMB), and institute of electrical and electronics engineers (IEEE) 802.16e communication standards.

As a representative example of such a broadband wireless communication system, the LTE system adopts orthogonal frequency division multiplexing (OFDM) for downlink and single carrier frequency division multiple access (SC-FDMA) for uplink. Uplink refers to a wireless link in which the user equipment (UE) (or mobile station (MS)) transmits data or control signals to the base station (BS) (or eNode B). Downlink refers to a wireless link in which the base station transmits data or control signals to the UE. Such a multiple access scheme may typically allocate and operate time-frequency resources carrying data or control information per user not to overlap (i.e., to maintain orthogonality, and to differentiate each user's data or control information).

The BS may be an entity allocating a resource to a terminal and may be at least one of a gNode B (gNB), an eNode B (eNB), a Node B, a radio access unit, a base station controller, or a node over network. The BS may be a network entity including at least one of an integrated access and backhaul-donor (IAB-donor), which is a gNB providing network access to UE(s) through a network of backhaul and access links in the new radio (NR) system, and an IAB-node, which is a radio access network (RAN) node supporting NR backhaul links to the IAB-donor or another IAB-node and supporting NR access link(s) to UE(s). The UE may be at least one of a terminal, an MS, a cellular phone, a smartphone, a computer, or a multimedia system capable of performing communication functions. The UE is wirelessly connected through the IAB-node and may transmit/receive data to and from the IAB-donor connected with at least one IAB-node through the backhaul link.

For ease of description, some of the terms or names defined in the 3GPP standards (standards for 5G, NR, LTE, or similar systems) may be used. However, the disclosure is not limited by such terms and names and may be likewise applicable to systems conforming to other standards. Further, the disclosure is not limited to the terms used in the following embodiments, and the terms may be replaced with other terms denoting objects with equivalent technical meanings.

1 FIG. is a diagram illustrating a method for UL enhancement, according to an embodiment.

In general, the UL has narrower coverage than the DL due to power limitations of the UE. This may act as a bottleneck in overall system coverage. In particular, in the case of the ‘above 6 GHz’ band (e.g., mmWave band/high band (24-92 GHz)/upper-mid band (7-24 GHz)), the coverage mismatch between these DL/UL may worsen.

To address the coverage mismatch, supplementary UL (SUL) technology may be used to secure UL coverage by additionally using a lower frequency band in UL than in DL.

1 FIG. 1 FIG. 1 FIG. For enhancement of UL capacity, a UL transmission (Tx) switching technology may be used together with the SUL technology. For example, as shown in, UL Tx switching for SUL may be applied. Referring to, not only the high band (e.g., 28 GHz band), but also the low/mid band (e.g., 2.1 GHz band) for SUL may be switched and used for UL transmission within coverage A. As shown in, UL Tx switching may be applied between two bands, but is not limited thereto. For example, UL Tx switching is applicable even between up to 3 or 4 bands.

A technique for UL enhancement, such as, for example, SUL/UL Tx switching, may use a plurality of UL carriers for UL transmission. Therefore, it is necessary to consider a method for selecting and accessing an appropriate UL carrier among a plurality of UL carriers. Further, a method for determining suitable UL power for UL transmission through the selected UL carrier may be considered.

An example of a scheme for UL carrier selection and UL transmission power determination may be a scheme based on measurement of a DL signal (DL measurement).

For example, UL coverage or UL carrier-based selection may be determined based on a comparison between DL reference signal received power (RSRP) measurement data and a preset threshold (e.g., rsrp-ThresholdSSB-SUL). The DL RSRP measurement data may be data (DL synchronization signal (SS)-RSRP measurement data) measured based on the DL synchronization signal block (SSB) (or a reference signal in the SSB), or data measured based on another reference signal (e.g., a channel state information reference signal (CSI-RS)).

For example, UL transmit power may be determined using the pathloss estimated based on the DL SSB or another reference signal (e.g., CSI-RS). Such pathloss estimation may use a known pathloss estimation method.

P i P i P PRACH,b,f,c CMAX,f,c PRACH,target,f,c b,f,c Equation (1) represents an example of a method for calculating physical random access channel (PRACH) transmission power based on pathloss.()=min{(),+PL}  (1)

PRACH,b,f,c CMAX,f,c PRACH,target,f,c b,f,c c Here, P(i) denotes the transmission power of the PRACH transmitted on the active UL bandwidth part (BWP) b of the carrier f of the serving cell c in the transmission occasion i. P(i) denotes the UE configured maximum output power for the carrier f of the serving cell cin the transmission occasion i. Pdenotes the PRACH target reception power (PREAMBLE_RECEIVED_TARGET_POWER) provided by higher layers for the active UL BWP b of the carrier f of the serving cell c. PLdenotes the pathloss estimation for the active UL BWP b of the carrier f based on the DL RS associated with PRACH transmission for the active UL BWP b of the serving cell c.

Equation (2) below represents an example of a method for calculating physical uplink shared channel (PUSCH) transmission power based on pathloss.

PUSCH,b,f,c d CMAX,f,c O-PUSCH,b,f,c O-NOMINIAL,PUSCH,f,c O-UE-PUSCH,b,f,c Here, P(i,j,q,l) denotes the transmission power in the PUSCH transmission occasion i of the PUSCH, transmitted on the active UL BWP b of the carrier f of the serving cell c using the parameter set configuration having index j and the PUSCH power control adjustment state having index l. P(i) denotes the UE-configured maximum output power for the carrier f of the serving cell c in the PUSCH transmission occasion i. P(j) denotes the parameter constituted of the sum of component P(j) and component P(j).

b,f,c d d b,f,c the bandwidth of the PUSCH resource allocation represented as the number of resource blocks for the PUSCH transmission occasion i on the active UL BWP b of the carrier f of the serving cell c. PL(q) denotes the DL pathloss estimation in dB calculated by the UE using the reference signal index qfor the active UL BWP b of the carrier f of the serving cell c. f(i,l) denotes the PUSCH power control adjustment state l for the active UL BWP b of the carrier f of the serving cell c and the PUSCH transmission occasion i.

However, when the DL band and the UL band are different, the accuracy of pathloss estimation and the accuracy of UL carrier selection (or UL coverage) may deteriorate. Therefore, it is necessary to consider a method for increasing the accuracy of pathloss estimation and UL carrier selection.

2 FIG. is a diagram illustrating a scenario for determining UL coverage and UL power using downlink (DL) measurement, according to an embodiment.

2 FIG. 2 FIG. In, it is assumed that the DL band and the UL band are different and that the UL band uses a lower frequency band than the DL band. For example, as shown in, the UL band may use a low/mid band (e.g., 800 MHz), and the DL band may use a high band (e.g., 28 GHz).

2 FIG. Referring to, the UE may perform DL measurement.

210 2 FIG. The UE may measure DL RSRP (e.g., DL SS-RSRP). In this case, as shown inof, when there is a blockage between the UE and the BS, inaccurate DL RSRP may be measured due to blocking of the reception signal by the blockage. As described above, DL RSRP measurement data may be used for UL coverage determination or UL carrier selection. For example, an appropriate UL carrier may be selected from among the SUL carrier and the normal UL (NUL) carrier based on a comparison between the DL SS-RSRP and a preset threshold (e.g., rsrp-ThresholdSSB-SUL).

220 2 FIG. Therefore, inaccurate DL SS-RSRP measurement may cause inaccurate UL coverage determination (or UL carrier selection). For example, inof, the UE may be estimated to be positioned farther from the base station than the actual location of the UE, and it may be determined that greater UL coverage is required.

2 FIG. 2 FIG. 230 The UE may estimate the pathloss based on the DL SSB (or another reference signal (e.g., CSI-RS)). In this case, as shown in, when there is a blockage between the UE and the base station, an inaccurate pathloss value may be estimated. Inaccurate path loss estimation may result in incorrect UL power allocation. For example, inof, the UE is allocated higher UL power because the UE is estimated to be positioned in a farther location than the actual location of the UE due to inaccurate pathloss estimation.

2 FIG. As such, as shown in, when the DL band and the UL band are different, inaccurate pathloss estimation and inappropriate UL carrier selection may be made. This may be an issue that arises as channel reciprocity is not established because a DL signal using a high band is vulnerable to blockage whereas a UL signal using a low/mid band is relatively robust to blockage.

Inaccurate UL transmission power allocation due to inaccurate pathloss estimation may cause unnecessary power consumption of the UE and aggravate UL interference. Further, inappropriate UL carrier selection due to inaccurate DL measurement may reduce the efficiency of resource use.

Therefore, when a plurality of UL carriers are used for UL enhancement, a method for obtaining accurate pathloss and accurate UL coverage (or UL carrier) needs to be considered.

The disclosure provides a method for obtaining UL pathloss data using a trained AI model, selecting/accessing an appropriate UL carrier from among a plurality of UL carriers using the obtained UL pathloss data, and efficiently controlling UL transmission power.

3 FIG. is a diagram illustrating a method for multiple UL carrier access, according to an embodiment.

A method for multiple UL carrier access may be a method using AI. For example, a method for multiple UL carrier access may be a method using UL pathloss data obtained using a pre-trained AI model. The AI model may be a deep learning-based model (e.g., a deep neural network (DNN), a recurrent neural network (RNN), a convolutional neural network (CNN)) and/or a machine learning-based model (e.g., support vector machine (SVM) or gradient boosting machine (GBM)).

3 FIG. 310 301 302 301 302 Referring to, at, a UEand a BSmay perform a cell access procedure. The cell access procedure may include a radio resource control (RRC) established procedure, an RRC reconfigured procedure, and/or an RRC re-established procedure. Thus, an RRC connection may be established between the UEand the BS.

320 302 301 At, the BSmay transmit AI model setup information to the UE. The AI model setup information may be referred to as AI UL inference setup information.

b AI model: The AI model parameter may be a parameter defining an AI model. The AI model may be an AI model having the pathloss(x; θ) of the base UL carrier as the output. The base UL carrier may be, for example, a UL carrier having the widest UL coverage among available UL carriers, but is not limited thereto. The AI model parameter may include hyperparameters for the AI model, such as, for example, the number of layers (#layers), the number of nodes (#nodes), an input/output format, and/or an activation function. The AI model parameter may be referred to as θ. Inference interval: The inference interval parameter may designate the period (UL inference period)/interval for performing UL inference using the AI model. Through UL inference using the AI model, pathloss data of the base UL carrier may be obtained periodically. b i UL carrier offset: The UL carrier offset parameter may designate the offset Δ between the pathloss(x; θ) of the base UL carrier and the pathlossof another UL carrier (e.g., the UL carrier having index i). The UL carrier offset parameter may be set for each UL carrier. The AI model setup information may include at least one of AI model parameters, inference interval/period parameters, UL carrier offset parameters, UL addition event parameters, UL release event parameters, or RACH indicator parameters. A description of each parameter is set forth below.

b i i b i x The relationship between the pathloss(x; θ) and the pathlossmay be as shown in Equation (3) below.=(;θ)+Δ   (3)

i b i 1 1 l U1 UL addition event: The UL addition event parameter may include information about an event for adding a new UL carrier. The event for adding a new UL carrier may be referred to as event U, addition event or UL addition event. The condition for event U(UL addition condition) may be as shown in Equation (4) below.<Thresh   (4) Here, x is the input (e.g., the DL RSRP measurement data (e.g., DL SS-RSRP) or UE location data (e.g., GPS data) or a combination of the DL RSRP measurement data and the UE location data) of the AI model, and θ is the AI model parameter. The pathlossof the UL carrier having index i corresponds to the sum of the AI model input x and the pathloss(x; θ) of the base UL carrier for the AI model parameter θ, and the UL carrier offset Δfor the UL carrier having index i.

U1 i U1 1 1 Here, Threshmay be a threshold for event U. According to Equation (4), when the pathlossof the UL carrier (e.g., the UL carrier having index i) is smaller than Thresh, event Umay be determined to meet the condition (UL addition condition).

U1 2 2 2 l U2 UL release event: The UL release event parameter may include information about an event for releasing an existing UL carrier (event U/release event). The event for releasing the UL carrier may be referred to as event U, release event or UL release event. The condition for event U(UL release condition) may be as shown in Equation (5) below.>Thresh   (5) The UL addition event parameter may include Thresh.

U2 i U2 2 2 Here, Threshmay be a threshold for event U. According to Equation (5), when the pathlossof the UL carrier (e.g., the UL carrier having index i) is larger than Thresh, event Umay be determined to meet the condition (UL release condition).

U2 RACH indicator: The RACH indicator parameter may be an indicator indicating whether operation is performed as contention free random access (CFRA) or RACH-less. For example, the RACH indicator parameter may be a Boolean indicator set to one of a first value (e.g., 1) indicating operation as CFRA or a second value (e.g., 0) indicating operation as RACH-less. The UL release event parameter may include Thresh.

The AI model setup information may be transmitted through an RRC message.

Table 1 shows an example of an RRC message including AI model setup information.

TABLE 1 RRCReconfiguration-IEs := SEQUENCE {  ...  measConfig  MeasConfig OPTIONAL, -- Need M  ...  ai-ul-inferConfig  AI-UL-InferConfig OPTIONAL, -- NEED M }

Referring to Table 1, AI model setup information (e.g., ai-ul-InferConfig) may be included in an RRC message or the RRCReconfiguration information element (IE) in the RRC message. The ai-ul-InferConfig information included in the RRC message may be an example of the above-described AI model setup information.

Table 2 illustrates an example of parameters included in the AI model setup information (e.g., ai-ul-InferConfig).

TABLE 2 AI-UL-InferConfig ::= SEQUENCE {  ai-ul-ModelConfig  AI-UL-ModelConfig OPTIONAL, -- Need N  InferIdToAddModList  InferIdToAddRodList OPTIONAL, -- Need N  InferIdToRemoveList  InferIdToAddModList OPTIONAL, -- Need N  ulAddReqConfig  UlAddReqConfig OPTIONAL, -- Need N  ulRelReqConfig  UlRelReqConfig OPTIONAL, -- Need N } AI-UL-ModelConfig ::= SEQUENCE {  modelId  ModelId,  baseUL  ULCarrierIndex  InferInterval  ENUMERATED {ms40, ms80, ...} } InferIdToRemoveList ::= SEQUENCE (SIZE (1..maxInferId) OF InferId InferIdToAddModList ::= SEQUENCE (SIZE (1..maxInferId) OF InferIdToAddMod InferIdToAddMod ::= SEQUENCE {  InferId  InferId,  InferObject  ULCarrierIndex,  InferOffset  INTEGER ( ) }

Referring to Table 2, the AI model setup information may include AI UL model setup parameters (e.g., ai-ul-ModelConfig), inference ID addition/modification list parameters (e.g., inferIDToAddModlist), inference ID removal list parameters (e.g., inferIDRemovelist), UL addition request setup parameters (e.g., ulAddReqConfig) and/or UL release request setup parameters (e.g., ulRelReqConfig).

The AI UL model setup parameters (e.g., ai-ul-ModelConfig) may include a model ID parameter (modelId) indicating the AI model ID (ModelId), a base UL parameter (baseUL) designating the base UL carrier, and/or an infer interval parameter (inferInterval) indicating the infer interval. The base UL parameter (baseUL) may include the index of the UL carrier used as the base UL carrier.

The inference ID addition/modification list parameters (e.g., inferIDToAddModlist) may include the sequence of the inference ID addition/modification parameter (e.g., inferIDToAddMod). The inference ID addition/modification parameters (e.g., inferIDToAddMod) may include an interference ID parameter (inferID) designating the interference ID, an interference object parameter (inferObject) indicating the index of the UL carrier associated with the interference ID, and/or an interference offset parameter (inferOffset) designating the infer offset. The inference ID may be used as an index to distinguish various pieces of inference configuration information.

The inference ID removal list (e.g., inferIDRemovelist) may be a sequence of inference ID parameters (InferId) to be removed.

Table 3 shows an example of a UL addition request configuration parameter (e.g., ulAddReqConfig) and a UL release request configuration parameter (e.g., ulRelReqConfig).

TABLE 3 UIAddReqConfig ::= SEQUENCE {  eventId  CHOICE {   eventU1   SEQUENCE {    u1-Threshold    InferredPathloss-Range,    hysteresis    Hysteresis,    timeToTrigger    TimeToTrigger   },  rachIndicator BOOLEAN  ....  } } UIRelReqConfig ::= SEQUENCE {  eventId  CHOICE {   eventU2   SEQUENCE {    u2-Threshold    InferredPathloss-Range,    hysteresis    Hysteresis,    timeToTrigger    TimeToTrigger   },  ....  } }

Referring to Table 3, the UL addition request configuration parameter (e.g., ulAddReqConfig) may include parameters for the UL carrier addition event (eventU1).

The UL addition request configuration parameter (e.g., ulAddReqConfig) may include a u1-Threshold parameter, a Hysteresis parameter, and/or a timeToTrigger parameter.

The u1-Threshold parameter may designate a threshold for an estimated pathloss for triggering eventU1.

The Hysteresis parameter is a parameter used for the entering condition and leaving condition of eventU1. The Hysteresis parameter in the UL addition request configuration parameter may be referred to as a first Hysteresis parameter. The entering condition of eventU1 may be referred to as a UL addition event entering condition, and the leaving condition of eventU1 may be referred to as a UL addition event leaving condition.

The timeToTrigger (TTT) parameter may designate a time (period) that should be met for eventU1 to be triggered. The TTT parameter in the UL addition request configuration parameter may be referred to as a second TTT parameter.

1 The entering condition of eventU1 (the UL addition event entering condition) may be as shown in Equation (6) below.PL+Hysteresis<Threshold   (6)

i 1 Here, PL denotes the estimated pathloss (e.g.,). Hysteresis denotes the value designated by the Hysteresis parameter (first Hysteresis parameter). Thresholddenotes the value designated by the u1-Threshold parameter.

1 The leaving condition of eventU1 may be as shown in Equation (7) below.PL−Hysteresis>Threshold   (7)

i 1 Here, PL denotes the estimated pathloss (e.g.,). The Hysteresis parameter denotes the value designated by the Hysteresis parameter (first Hysteresis parameter). Thresholddenotes the value designated by the u1-Threshold parameter.

When the entering condition of eventU1 is met, a timer set to a time (period) designated by the TTT parameter (e.g., first TTT parameter) may be started.

The eventU1 may be triggered when the timer set to the time (period) designated by the TTT parameter (e.g., first TTT parameter) expires after the entering condition of eventU1 is met. Specifically, a UL addition procedure for the corresponding UL carrier may be initiated.

If the leaving condition of eventU1 is met after the entering condition of eventU1 is met and before the timer set to the time (period) designated by the TTT parameter (the first TTT parameter) expires, eventU1 is not triggered. In this case, the timer set to the time (period) designated by the TTT parameter (first TTT parameter) may be reset.

As the event for the UL addition request, eventU1 has been used as an example, but embodiments are not limited thereto.

Further, the UL addition request configuration parameters (e.g., ulAddReqConfig) may further include an RACH indicator parameter.

The UL release request configuration parameters (e.g., ulRelReqConfig) may include parameters for the UL carrier release event (eventU2).

The UL release request configuration parameters (e.g., ulRelReqConfig) may include a u2-Threshold parameter, a Hysteresis parameter, and/or a TTT parameter.

The u2-Threshold parameter may designate a threshold for an estimated pathloss for triggering eventU2.

The Hysteresis parameter is a parameter used for the entering condition and leaving condition of eventU2. The Hysteresis parameter in the UL release request configuration parameter may be referred to as a second Hysteresis parameter. The entering condition of eventU2 may be referred to as a UL release event entering condition, and the leaving condition of eventU2 may be referred to as a UL release event leaving condition. The value of the second Hysteresis parameter for UL release may be the same as or different from the value of the first Hysteresis parameter for UL addition.

The TTT parameter may designate the time that should be met for eventU2 to be triggered. The TTT parameter in the UL release request configuration parameters may be referred to as a second TTT parameter. The value of the second TTT parameter for UL release may be the same as or different from the value of the first TTT parameter for UL addition.

2 The entering condition of eventU2 (e.g., the UL release event entering condition) may be as shown in Equation (8) below.PL−Hysteresis<Threshold   (8)

i Here, PL denotes the estimated pathloss (e.g.,). Hysteresis denotes the value designated by the Hysteresis parameter (second Hysteresis parameter). Threshold denotes the value designated by the u2-Threshold parameter.

2 The leaving condition of eventU2 may be as shown in Equation (9) below.PL+Hysteresis>Threshold   (9)

i Here, PL denotes the estimated pathloss (e.g.,). Hysteresis denotes the value designated by the Hysteresis parameter (second Hysteresis parameter). Threshold denotes the value designated by the u1-Threshold parameter.

When the entering condition of eventU2 is met, a timer set to a time (period) designated by the TTT parameter (second TTT parameter) may be started.

The eventU2 may be triggered when the timer set to the time (period) designated by the TTT parameter (second TTT parameter) expires after the entering condition of eventU2 is met. Specifically, a UL release procedure for the corresponding UL carrier may be initiated.

If the leaving condition of eventU2 is met after the entering condition of eventU2 is met and before the timer set to the time (period) designated by the TTT parameter (the second TTT parameter) expires, eventU2 is not triggered. In this case, the timer set to the time (period) designated by the TTT parameter (second TTT parameter) may be reset.

As the event for the UL release request, eventU2 has been used as an example, but embodiments are not limited thereto.

Further, the UL release request configuration parameter (e.g., ulRelReqConfig) may further include an RACH indicator parameter.

Further, the RRC message for AI model setup may further include quantity configuration information (e.g., QuantityConfig).

Table 4 shows an example of the quantity configuration information (e.g., QuantityConfig).

TABLE 4 QuantityConfig ::= SEQUENCE {  quantityConfigNR-List  SEQUENCE (SIZE (1..maxNrOfQuanityConfig)) OF QuantityConfigNR  ...,  quantityConfigAI-UL  QuantityConfigAI-UL } QuantiyConfigAI-UL ::= SEQUENCE {  filterCoefficientAI-UL  FilerCoefficient  DEFAULT fc4, }

Referring to Table 4, the quantity configuration information (e.g., QuantityConfig) may include a quantityConfigAI-UL parameter. The quantityConfigAI-UL parameter may be used to configure the measurement quantity and L3 filtering coefficient for AI-based inference.

The quantityConfigAI-UL parameter (or Quantity configuration information) may include a filterCoefficientAI-UL parameter. The filterCoefficientAI-UL parameter may designate the L3 filtering coefficient for AI UL.

3 FIG. 330 301 301 Referring back to, at, the UEmay perform UL inference based on the AI model (AI-based UL inference). The UEmay perform periodic UL inference according to the period set by the inference interval parameter, but embodiments are not limited thereto.

301 301 Through the AI-based UL inference, the UEmay obtain/estimate pathloss data for the base UL carrier. Further, the UEmay obtain pathloss data for UL carrier(s) other than the base UL carrier based on the pathloss data for the base UL carrier and the value of the UL carrier offset parameter. Here, the pathloss data may include a specific value or range of values for pathloss. The pathloss value obtained through AI-based UL inference (or estimation) has a more accurate value than the pathloss value estimated by simple DL measurement. Herein, the UL pathloss data inferred/estimated based on the AI model may be denoted as AI-inferred UL pathloss data, AI-inferred pathloss data, AI-estimated pathloss data or estimated pathloss data.

Pathloss data may be used to determine whether the UL addition condition or the UL release condition is met. Equation (4) (or Equation (6)/(7)) may be used to, for example, determine whether the UL addition condition is met. To determine whether the UL release condition is met, Equation (5) (or Equation (8)/(9)) may be used, for example.

i b,f,c b,f,c d The pathloss data may be used to determine power for UL transmission (UL transmission power) using the selected UL carrier. To determine the UL transmission power based on the pathloss data, Equation (1) or Equation (2) may be used, for example. In this case, the pathloss valueof the UL carrier may be used as the value PLof Equation (1) or the value PL(q) of Equation (2).

4 6 FIGS.to Examples of AI-based UL inference are described below with reference to.

340 301 301 3 FIG. 7 9 FIGS.to Atof, the UEmay perform a UL addition procedure. The UL addition procedure may be a conditional procedure. The UEmay determine whether the UL addition condition is met using the pathloss data obtained based on the AI-based UL inference and, when the UL addition condition is met, perform a procedure for adding a new UL carrier. Examples of the UL carrier addition procedure are described below with reference to.

350 301 301 10 11 FIGS.and At, the UEmay perform a UL release procedure. The UL addition procedure may be a conditional procedure. The UEmay determine whether the UL release condition is met using the pathloss data obtained based on the AI-based UL inference and, when the UL release condition is met, perform a procedure for releasing an existing UL carrier. Examples of the UL carrier release procedure are described below with reference to.

According to the method for multiple UL carrier access of the disclosure, it is possible to add/release one or more UL carriers using the exact pathloss data obtained/estimated through AI-based UL inference. In this case, a plurality of UL carriers may be configured. Thus, it is possible to support flexible UL Tx switching and select an appropriate UL carrier.

Further, according to the method for multiple UL carrier access, it is possible to perform accurate UL power control using the exact pathloss data obtained through AI-based UL inference. This may reduce UL interference and prevent unnecessary UE power consumption.

3 FIG. 340 350 According to embodiments, some of the operations (or steps) shown inmay be omitted or additional operations may be included. For example, when the UL addition condition is not met, the UL addition procedure ofmay not be performed. When the UL release condition is not met, the UL release procedure ofmay not be performed. Further, the operations (or steps) may be performed in an order different from the order shown.

4 FIG. is a diagram illustrating a scenario for AI-based UL inference, according to an embodiment.

4 FIG. 301 302 302 In the case of, the UEmay receive DL signals from the BS (a serving cell)and at least one neighbor cell (e.g., neighbor cell ½). The serving cellmay use the FR2 band for DL/UL and may use the FR1 band for UL (e.g., SUL), but is not limited thereto. As shown, some of the received DL signals may be blocked by blockage.

4 FIG. 301 Referring to, the UEmay infer the pathloss for the base UL carrier (e.g., a UL carrier using the FR1 band) using the AI model. The input of the AI model used for pathloss inference for the base UL carrier may include not only the DL RSRP data (e.g., DL SS-RSRP data) of the serving cell, but also the DL RSRP data (e.g., DL SS-RSRP data) of the neighbor cell(s). Accurate pathloss data may be obtained through this AI-based inference. Thus, flexible UL Tx switching and UL transmission power control may be performed.

5 FIG. is a flowchart illustrating a procedure for performing AI-based UL inference by a UE, according to an embodiment.

5 FIG. 3 FIG. 330 The AI-based UL inference procedure ofmay be an example ofof.

5 FIG. Referring to, a procedure for performing AI-based UL inference (AI-based UL inference procedure) may include some or all of the following operations or steps.

510 510 320 5 FIG. 3 FIG. At, the UE may receive AI model setup information from the base station. The AI model setup information ofofmay be the same as the AI model setup information ofof.

520 520 At, the UE may determine whether a radio resource management (RRM) measurement period is met. When the RRM measurement period is not met, the determination may be performed again at.

530 When the RRM measurement period is met, the UE may measure DL RSRP, at. For example, the UE may measure the beam-level DL SS-RSRP based on the SSB (or the reference signal included in the SSB). The UE may also measure DL RSRP based on another reference signal (e.g., CSI-RS).

540 At, the UE may perform filtering (e.g., L1 filtering) on DL RSRP measurement data. This filtering operation may be optional.

550 520 At, the UE may determine whether the UL inference period is met. The UE may determine whether the UL inference period is met based on the value of the Inference interval parameter. When the UL reasoning period is not met, the determination may be performed again at.

560 When the UL reasoning period is met, the UE may perform UL pathloss inference (AI-based UL inference) based on the DL RSRP measurement data (or filtered DL RSRP measurement data), at. The UE may infer (or estimate) the pathloss for the UL carrier using the pre-trained AI model. The AI model may be configured by the AI model setup information. The UE may obtain pathloss data for the base UL carrier using the pre-trained AI model based on the DL RSRP measurement data (or filtered DL RSRP measurement data) and obtain pathloss data for the base UL carrier and pathloss data for other UL carriers using the value of the UL carrier offset parameter. In this case, the DL RSRP measurement data (or filtered DL RSRP measurement data) may be used as an input of the AI model.

570 At, the UE may perform evaluation on the UL addition event and/or UL release event. The UE may determine whether the UL addition event meets a preset condition (UL addition condition) and/or whether the UL release event meets a preset condition (UL release condition) based on the inferred pathloss data. Thus, the UL addition event and/or the UL release event is triggered, so that a UL addition procedure and a UL release procedure may be performed.

5 FIG. 540 510 520 Some of the operations shown inmay be omitted or additional operations may be included. For example,may be omitted as an optional operation.may be a separate operation performed before the AI-based UL inference procedure, andmay be a separate operation performed after the AI-based UL inference procedure. Further, the operations may be performed in an order different from the order shown.

6 FIG. is a diagram illustrating an AI model for AI-based UL inference, according to an embodiment.

6 FIG. 6 FIG. 4 FIG. 600 610 1 1 1 1 1 2 2 The AI model ofshows an example of an AI model using DL RSRP measurement data (e.g., beam level SS-RSRP measurement data) as an input. Referring to, an AI modelmay receive N*M-sized DL SS-RSRP measurement data as an input. For example, in the case of having the arrangement structure of, the DL SS-RSRP data may include, but is not limited to, DL SS-RSRP measurement values for SSBto SSBn of the serving cell, DL SS-RSRP measurement values for SSBto SSBm of neighbor cell(NCell), and/or DL SS-RSRP measurement values for SSBto SSBl of neighbor cell(NCell).

600 620 The AI modelmay generate probability values for K low-band UL pathloss ranges for the base UL carrier as an output.

620 The UE may determine that the low-band UL pathloss range having the highest probability value among the probability values included in the outputis the pathloss range of the base UL carrier corresponding to the corresponding input. Further, the UE may determine a pathloss range for a UL carrier other than the base UL carrier, using the UL carrier offset parameter.

6 FIG. As described above, in the example of, for convenience of description, DL SS-RSRP measurement data is used as an input of the AI model, but embodiments are not limited thereto. For example, DL RSRP measurement data measured based on other reference signals (e.g., CSI-RS) may also be used as an input of the AI model. For example, location information about the UE (e.g., GPS-based location data (GPS data)) may be used as an input of the AI model. For example, a combination of the DL RSRP data (e.g., DL SS-RSRP or DL RSRP data based on another reference signal) and location information about the UE may be used as an input of the AI model.

6 FIG. Further, in, it is described that pathloss ranges are used as output labels of the AI model, but embodiments are not limited thereto. For example, specific pathloss values may be used as output labels.

7 FIG. is a diagram illustrating a scenario for UL carrier addition, according to an embodiment.

7 FIG. In, for convenience of description, it is assumed that three UL carriers are used. For example, as shown, a UL carrier using a 28 GHz band (UL carrier 1), a UL carrier using a 2.1 GHz band (UL carrier 2), and a UL carrier using an 800 MHz band (UL carrier 3) may be used. Among them, one UL carrier may be used as a base UL carrier. For example, UL carrier 3 having the widest coverage may be set as the base UL carrier.

7 FIG. 301 700 302 1 301 As shown in, when the UEmoves closerto the BS, an event for adding a UL carrier (event U) may meet a preset condition (UL addition condition). For example, when the UE, located outside the UL coverage of UL carrier 2, moves within the UL coverage of UL carrier 2, an event for adding UL carrier 2 may meet a preset condition. Equation (4) (or Equation (6)/(7)) may be used to, for example, determine whether the UL addition condition is met. In this case, the value of pathloss data for UL carrier 2 may be obtained by adding the value of the UL carrier offset for UL carrier 2 set by the UL carrier offset parameter to the pathloss data value for UL carrier 3, which is the base UL carrier obtained using the AI model.

1 301 302 When the UL addition condition is met (i.e., when the UL addition event (event U) is triggered), the UEand the BSmay perform a procedure for adding a new UL carrier.

8 FIG. is a diagram illustrating a procedure for UL carrier addition, according to an embodiment.

8 FIG. 3 FIG. 8 FIG. 8 FIG. 340 The UL carrier addition procedure ofmay be an example ofof. The UL carrier addition procedure ofmay be a UL carrier addition procedure operating as CFRA. In, CFRA may be performed after transmission of a UL addition request message using the base UL carrier of the UE.

8 FIG. 810 301 301 301 Referring to, at, the UEmay identify that the UL addition condition is met. For example, the UEmay identify that the UL addition condition of Equation (4) is met. Alternatively, when the UL addition event entering condition of Equation (6) is met, and a preset period (e.g., the period set by the TTT parameter) elapses, the UEmay identify that the UL addition condition is met.

820 301 302 301 301 At, the UEmay transmit a UL addition request message to the BS. The UEmay transmit a UL addition request message using the base UL carrier. For example, the UEmay transmit a UL addition request message through the PUSCH using the base UL carrier.

1 The UL addition request message may include UL carrier index information about an addition event (event U), AI-based UL inferred (AI-inferred) UL pathloss information, and/or PUSCH transmission power information.

Here, the UL carrier index information about the addition event may include the index of a UL carrier to be added when the UL addition condition is met.

302 302 The AI-inferred UL pathloss information may include an AI-inferred/estimated UL pathloss value (e.g., a UL pathloss range value) for the base UL carrier (or a UL carrier to be added). When the AI-inferred/estimated UL pathloss value for the base UL carrier is transferred to the base station, the BSmay obtain/calculate the AI-inferred/estimated UL pathloss value for the corresponding UL carrier using the UL carrier offset parameter value for the corresponding UL carrier.

The PUSCH transmission power information may include the transmission power value of the PUSCH through which the UL addition request is transmitted.

830 302 302 At, the BSmay perform admission control on the UL carrier to be added. Through admission control, the BSmay determine whether the UL carrier to be added may receive the corresponding UE.

840 302 302 At, the BSmay transmit a preamble assignment message. The BSmay transmit a preamble assignment message through the PDSCH. The preamble assignment message is an RRC message and may serve as a UL addition command for the UL addition request message.

The preamble assignment message may include information for assigning a preamble to be transmitted on a new UL carrier.

1 1 1 302 The preamble assignment message may optionally further include transmit power control (TPC) information for MSG(MSG_PRACH) for random access. The TPC information for MSGmay include a power correction value obtained based on a comparison between PUSCH-related power information and AI-inferred UL pathloss information in the UL addition request message. The PUSCH-related power information may be a value corresponding to a difference between the PUSCH reception power measured by the base station(e.g., the reception power of the PUSCH including the UL addition request message) and the PUSCH transmission power in the UL addition request message.

1 1 1 1 The preamble assignment message may optionally further include RACH configuration information about the new UL carrier. In this case, system information block(SIB) broadcasted by the base station may include only RACH configuration information about the base UL carrier. RACH configuration information about the remaining UL carriers other than the base UL carrier may be included in the preamble assignment message for the corresponding UL carrier and transmitted. Thus, the overhead of SIBmay be reduced. Instead, SIBmay include RACH configuration information about all the UL carriers. In this case, the preamble assignment message does not include RACH configuration information about the new UL carrier. The RACH configuration information may include, for example, the number of SSBs per RACH occasion for the UL carrier and the number of preambles per SSB.

840 301 1 302 301 301 At, the UEmay transmit a preamble (MSG) to the BS. The UEmay transmit a preamble using a new UL carrier. For example, the UEmay transmit a preamble through PRACH using the new UL carrier.

850 302 2 301 302 860 At, the BSmay transmit a random access response (RAR)(MSG) to the UE. The BSmay transmit the RAR through the PDSCH, at.

The RAR may include a timing advance (TA) command and/or a training data collection indicator of the new UL carrier. The training data collection indicator may also be referred to as a data request indicator. The training data collection indicator or data request indicator may be set to a first value (e.g., 1) indicating a request (data request) for training data (sample) or a second value (e.g., 0) not indicating a request (data request) for training data (sample).

9 FIG. is a diagram illustrating a procedure for UL carrier addition, according to an embodiment.

9 FIG. 3 FIG. 9 FIG. 340 The UL carrier addition procedure ofmay be an example ofof. The UL carrier addition procedure ofmay be a UL carrier addition procedure operating as RACH-less.

9 FIG. 910 301 301 301 Referring to, at, the UEmay identify that the UL addition condition is met. For example, the UEmay identify that the UL addition condition of Equation (4) is met. Alternatively, when the UL addition event entering condition of Equation (6) is met, and a preset period (e.g., the period set by the timeToTrigger parameter) elapses, the UEmay identify that the UL addition condition is met.

920 301 302 301 301 At, the UEmay transmit a UL addition request message to the BS. The UEmay transmit a UL addition request message using the base UL carrier. For example, the UEmay transmit a UL addition request message through the PUSCH using the base UL carrier.

301 302 1 8 FIG. For example, the UEmay transmit a UL addition request message for UL addition to the BSthrough an RRC message. The UL addition request message may include UL carrier index information about an addition event (event U), AI-based UL inferred (AI-inferred) UL pathloss information, and/or PUSCH transmission power information. For a description of each piece of information, reference may be made to the description of.

301 302 301 302 1 302 302 As another example, the UEmay transmit a UL carrier activation request for UL carrier activation to the BSthrough a MAC CE. For example, when a previously configured UL carrier between the UEand the BSmeets an addition event (event U), the UEmay transmit a UL carrier activation request to the BSusing the MAC CE instead of an RRC message.

930 302 302 At, the BSmay perform admission control on the UL carrier to be added. Through admission control, the BSmay determine whether the UL carrier to be added may receive the corresponding UE.

940 302 301 At, the BSmay transmit a message indicating that the addition of the UL carrier is complete (UL addition complete message) to the UE.

10 FIG. is a diagram illustrating a scenario for UL carrier release, according to an embodiment.

10 FIG. In, for convenience of description, it is assumed that three UL carriers are used. For example, as shown, a UL carrier (UL carrier 1) using a 28 GHz band, a UL carrier (UL carrier 2) using a 2.1 GHz band, and a UL carrier (UL carrier 3) using an 800 MHz band may be used. Among them, one UL carrier may be used as a base UL carrier. For example, UL carrier 3 having the widest coverage may be set as the base UL carrier.

10 FIG. 301 1000 302 2 301 As shown in, when the UEmoves awayfrom the BS, an event for releasing a UL carrier (event U) may meet a preset condition (UL release condition). For example, when the UElocated within the UL coverage of UL carrier 2 moves out of the UL coverage of UL carrier 2, the event for releasing UL carrier 2 may meet the preset condition. To determine whether the UL release condition is met, Equation (5) (or Equation (8)/(9)) may be used, for example. In this case, the value of pathloss data for UL carrier 2 may be obtained by adding the UL carrier offset for UL carrier 2 set by the UL carrier offset parameter to the pathloss data value for UL carrier 3 which is the base UL carrier obtained using the AI model.

2 301 302 When the UL release condition is met (i.e., when the UL release event (event U) is triggered), the UEand the BSmay perform a procedure for releasing an existing UL carrier.

11 FIG. is a diagram illustrating a procedure for UL carrier release, according to an embodiment.

11 FIG. 3 FIG. 350 The UL carrier release procedure ofmay be an example ofof.

11 FIG. 1110 301 301 301 Referring to, at, the UEmay identify that the UL release condition is met. For example, the UEmay identify that the UL release condition of Equation (5) is met. Alternatively, when the UL release event entering condition of Equation (8) is met, and a preset period (e.g., the period set by the TTT parameter) elapses, the UEmay identify that the UL release condition is met.

1120 301 302 301 301 At, the UEmay transmit a UL release request message to the BS. The UEmay transmit a UL release request message using the base UL carrier. For example, the UEmay transmit a UL release request message through the PUSCH using the base UL carrier.

1130 302 301 At, the BSmay transmit a message indicating that the release of the UL carrier is complete (UL addition complete message) to the UE.

12 FIG. is a diagram illustrating a data collection procedure for training an AI model, according to an embodiment.

12 FIG. 12 FIG. The embodiment ofshows an example of periodic (or random) training data collection. The training data collection procedure ofmay be suitable for collecting data for initial AI model training. The initial training of the AI model may be performed by the base station or a server connected to the base station, but is not limited thereto.

12 FIG. 1210 302 302 Referring to, at, the BSmay identify that data collection (or data collection event) is triggered. The BSmay identify that data collection (or data collection event) is triggered when a preset condition (e.g., periodic condition) is met.

1220 302 301 302 302 At, the BSmay transmit a data request message to the UE. The BSmay select a UE to request for data when it is identified that data collection (or data collection event) is triggered. The BSmay select all the UEs or some randomly selected UEs as UEs to request for data.

1230 301 302 At, the UEmay transmit a reference signal and a PUSCH to the BS. The reference signal may be a sounding reference signal (SRS), but embodiments are not limited thereto. Hereinafter, for convenience of description, it is assumed that the reference signal is the SRS.

The PUSCH may include data (e.g., DL RSRP measurement data (e.g., DL SS-RSRP measurement data) or UE location data (e.g., GPS data)) to be used as an input (X data) of an AI model to be trained.

302 301 320 3 FIG. The SRS may be used by the base stationto estimate UL pathloss. The UL pathloss estimated based on the SRS may be used as an output (Y label/actual value) for training the AI model. For example, the AI model may be trained to reduce the difference (error) between the UL pathloss (actual value) estimated based on the SRS and the AI-based UL inferred (AI-inferred) UL pathloss (inferred value) based on the input (X data). The configuration information for the so trained AI model may be transmitted to the UEthrough the above-described AI model setup information (e.g., the AI model setup information ofin).

13 FIG. is a diagram illustrating another example of a data collection procedure for training an AI model, according to an embodiment.

13 FIG. 13 FIG. shows an example of threshold-based training data collection. The training data collection procedure ofmay be suitable for collecting additional data for fine-tuning of the AI model that is running. The fine tuning of the AI model may be performed by the BS or a server connected to the BS, but is not limited thereto.

13 FIG. 1310 301 301 301 Referring to, at, the UEmay identify that the UL addition condition is met. For example, the UEmay identify that the UL addition condition of Equation (4) is met. Alternatively, when the UL addition event entering condition of Equation (6) is met, and a preset period (e.g., the period set by the TTT parameter) elapses, the UEmay identify that the UL addition condition is met.

1320 301 302 1320 820 8 FIG. At, the UEmay transmit a UL addition request message to the BS. The UL addition request message ofmay be identical to the UL addition request message ofof.

1330 302 302 302 302 8 FIG. At, the BSmay perform evaluation of AI results. For example, the BSmay determine whether the result of comparison between PUSCH-related power information and AI-inferred UL pathloss information (e.g., pathloss range value) in the UL addition request message is equal to or larger than a threshold. Here, the PUSCH-related power information may be a value corresponding to a difference between the PUSCH reception power measured by the BS(e.g., the reception power of the PUSCH including the UL addition request message) and the PUSCH transmission power in the UL addition request message. When the result of comparison between the PUSCH-related power value and the AI-inferred UL pathloss value in the UL addition request message is larger than or equal to the threshold, the BSmay set the value of the training data collection indicator (data request indicator) in the RAR to the first value (e.g., 1) to indicate a request for training data. A description of the training data collection indicator (data request indicator) may refer to.

1340 302 1340 840 13 FIG. 8 FIG. At, the BSmay transmit a preamble assignment message. The preamble assignment message ofofmay be identical to the preamble assignment message ofof.

1350 301 1 302 1350 840 13 FIG. 8 FIG. At, the UEmay transmit a preamble (MSG) to the BS. The preamble ofofmay be identical to the preamble ofof.

1360 302 2 301 At, the BSmay transmit an RAR (MSG) to the UE. As described above, the RAR may include a training data collection indicator (data request indicator). The value of the training data collection indicator (data request indicator) may be set to the first value (e.g., 1) indicating a data request.

1370 301 302 301 302 At, the UEmay transmit a reference signal (e.g., SRS) and a PUSCH to the BS. For example, when the value of the training data collection indicator (data request indicator) in the RAR is set to the first value (e.g., 1) indicating a data request, the UEmay transmit the SRS and PUSCH to the BS.

The PUSCH may include data (e.g., DL RSRP measurement data (e.g., DL SS-RSRP measurement data) or UE location data (e.g., GPS data)) to be used as an input (X data) of an AI model to be trained.

302 301 320 3 FIG. The SRS may be used by the BSto estimate UL pathloss. The UL pathloss estimated based on the SRS may be used as an output (Y label/actual value) for training the AI model. For example, the AI model may be trained to reduce the difference (error) between the UL pathloss (actual value) estimated based on the SRS and the AI-based UL inferred (AI-inferred) UL pathloss (inferred value) based on the input (X data). The configuration information for the so trained AI model may be transmitted to the UEthrough the above-described AI model setup information (e.g., the AI model setup information ofin).

14 FIG. is a flowchart illustrating a method by a UE, according to an embodiment.

14 FIG. 3 FIG. 320 1410 Referring to, the UE may receive AI model setup information (e.g., the AI model setup information ofin) for estimating AI-based UL pathloss from the BS, at.

1420 The UE may estimate AI-based UL pathloss for the base UL carrier based on the AI model setup information, at.

The AI model setup information may include at least one of information on an AI model used for estimating the AI-based UL pathloss, period information for estimating the AI-based UL pathloss, offset information designating an offset between AI-based UL pathloss for the base UL carrier and AI-based UL pathloss for the corresponding UL carrier, information about a UL carrier addition event, or information about a UL carrier release event.

The AI model setup information may further include indicator information indicating whether UL carrier addition is operated as CFRA or RACH-less.

The AI model setup information may be transmitted through an RRC message.

The UE may determine whether a condition for adding a new UL carrier is met based on the AI-based UL pathloss and, when the condition for adding a new UL carrier is met, add the new UL carrier.

The UE may transmit a UL carrier addition request message for the new UL carrier to the base station, receive a preamble assignment message for assigning a preamble to be transmitted to the new UL carrier from the base station, transmit the preamble, and receive a random access response corresponding to the preamble.

The UL carrier addition request message may include UL carrier index information about a new UL carrier to be added, information about the AI-based UL pathloss, and transmission power information about the PUSCH where the UL carrier addition request message is transmitted.

The random access response may include indication information indicating whether to request training data to be used for training an AI model used for estimation of the AI-based UL pathloss. When the indication information is set to a value indicating to request the training data, the UE may transmit a SRS and a PUSCH to the base station.

The UE may determine whether a condition for releasing an existing UL carrier is met based on the AI-based UL pathloss.

The AI model used for estimation of the AI-based UL pathloss may use the DL RSRP measured based on the DL signal received from the serving cell and at least one neighbor cell or location data of the UE, as input data.

15 FIG. is a diagram illustrating an example of a configuration of a UE in a wireless communication system, according to an embodiment.

15 FIG. 7 FIG. 1 14 FIGS.to 1501 1503 1505 1501 1503 1505 1501 1503 1505 In, a UE may include a processor, a transceiver, and a memory. The processor, transceiver, and memoryof the UE ofmay be operated according to the method(s) described above in connection with. However, the components of the UE are not limited thereto. For example, the UE may include more or fewer components than the above-described components. The processor, the transceiver, and the memorymay be implemented in the form of at least one chip.

1503 1503 510 1503 1503 1501 1501 1503 1501 1501 The transceivercollectively refers to a receiver and a transmitter and may transmit and receive signals to/from a UE or another network entity. The transmitted/received signals may include at least one of control information and data. To that end, the transceivermay include an RF transmitter for frequency-up converting and amplifying signals transmitted and an RF receiver for low-noise amplifying signals received and frequency-down converting the frequency of the received signals. This is merely an embodiment of the transceiver, and the components of the transceiverare not limited to the RF transmitter and the RF receiver. Further, the transceivermay receive signals through a communication scheme defined in the 3GPP standard, output the signals to the processor, and transmit the signals output from the processor. Further, the transceivermay receive the signal and output it to the processorand transmit the signal output from the processorto another network entity through the network.

1505 1505 1505 1 14 FIGS.to The memorymay store programs and data necessary for the operation of the UE according to at least one of the embodiments of. The memorymay store control information and/or data that is included in the signal obtained by the UE. The memorymay include a storage medium, such as ROM, RAM, hard disk, CD-ROM, and DVD, or a combination of storage media.

1501 1501 1 14 FIGS.to The processormay control a series of processes so that the UE may operate according to at least one of the embodiments of. The processormay include at least one processor.

16 FIG. is a diagram illustrating an example of a configuration of a BS in a wireless communication system, according to an embodiment.

16 FIG. 7 FIG. 1 14 FIGS.to 1601 1603 1605 1601 1603 1605 1601 1603 1605 In, a BS may include a processor, a transceiver, and a memory. The processor, transceiver, and memoryof the UE ofmay be operated according to the method(s) described above in connection with. However, the components of the BS are not limited thereto. For example, the BS may include more or fewer components than the above-described components. The processor, the transceiver, and the memorymay be implemented in the form of at least one chip.

1603 1603 1603 1603 1603 1601 1601 1603 1601 1601 The transceivercollectively refers to a receiver and a transmitter and may transmit and receive signals to/from a UE or another network entity. The transmitted/received signals may include at least one of control information and data. To that end, the transceivermay include an RF transmitter for frequency-up converting and amplifying signals transmitted and an RF receiver for low-noise amplifying signals received and frequency-down converting the frequency of the received signals. This is merely an embodiment of the transceiver, and the components of the transceiverare not limited to the RF transmitter and the RF receiver. Further, the transceivermay receive signals through a communication scheme defined in the 3GPP standard, output the signals to the processor, and transmit the signals output from the processor. Further, the transceivermay receive the signal and output it to the processorand transmit the signal output from the processorto another network entity through the network.

1605 1605 1505 1 14 FIGS.to The memorymay store programs and data necessary for the operation of the BS according to at least one of the embodiments of. The memorymay store control information and/or data that is included in the signal obtained by the UE. The memorymay include a storage medium, such as ROM, RAM, hard disk, CD-ROM, and DVD, or a combination of storage media.

1601 1601 1 14 FIGS.to The processormay control a series of processes so that the base station may operate according to at least one of the embodiments of. The processormay include at least one processor.

In the above-described specific embodiments, the components included in the disclosure are represented in singular or plural forms depending on specific embodiments proposed. However, the singular or plural forms are selected to be adequate for contexts suggested for ease of description, and the disclosure is not limited to singular or plural components. As used herein, the singular forms “a,” “an,” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise.

Although specific embodiments of the present disclosure have been described above, various changes may be made thereto without departing from the scope of the present disclosure. Thus, the scope of the disclosure should not be limited to the above-described embodiments, and should rather be defined by the following claims and equivalents thereof.